Arrow rests are employed to hold the arrow in position until a bow is fired. This makes for a more accurate shot than positioning the arrow with the archer's hand does.
Three types of arrow rests are available: shoot-thru, containment, and fall-away.
Shoot-thru rests have the disadvantage that a fletch may contact the rest as the arrow passes through it. This can disrupt the flight of the arrow, leading to an inaccurate shot, and can damage the fletch. Also, there is nothing to keep the arrow from falling off the rest.
Some containment rests also allow the fletching to contact the rest, leading to fletch damage and an inaccurate shot when the bow is fired. Containment rests designed to eliminate fletch-and-rest contact require precise nock and fletching alignment and can be difficult to use.
Unlike shoot-thru rests, fall-away rests hold the arrow firmly in position until the bow is fired. At this point, drop out of the path of the arrow, eliminating fletch clearance problems.